error:
       … while evaluating the attribute 'optionalValue.value'
         at «git+https://github.com/NixOS/nixpkgs?ref=nixpkgs-unstable&rev=3d8f0f3f72a6cd4d93d0ad13203f2ea1cb7e1456&shallow=1»/lib/modules.nix:1330:5:
         1329|
         1330|     optionalValue = if isDefined then { value = mergedValue; } else { };
             |     ^
         1331|   };

       … while evaluating a branch condition
         at «git+https://github.com/NixOS/nixpkgs?ref=nixpkgs-unstable&rev=3d8f0f3f72a6cd4d93d0ad13203f2ea1cb7e1456&shallow=1»/lib/modules.nix:1330:21:
         1329|
         1330|     optionalValue = if isDefined then { value = mergedValue; } else { };
             |                     ^
         1331|   };

       … while evaluating definitions from `/nix/store/xfg4bws749i95jvnxhymxmfwailzk38q-source/modules/transposition.nix':

       … while evaluating definitions from `/nix/store/pwzv0gvph47cya8jdjhp3vnh0dsxq2mh-source/checks/flake-module.nix, via option perSystem':

       … while evaluating the option `system.build.toplevel':

       … while evaluating definitions from `/nix/store/yijgvcly3sdvj90y55w6qd7lcihzy36s-source/nixos/modules/system/activation/top-level.nix':

       … while evaluating the option `assertions':

       … while evaluating definitions from `/nix/store/c1ka0xdxj00wakzkqx8ccpkjjcjsnkmc-source/modules/sops':

       … while evaluating the option `sops.secrets':

       … while evaluating definitions from `/nix/store/amd6azqbxnz6j41892kjx8b6y9hz3pmb-source/nixosModules/clanCore/vars/secret/sops':

       (stack trace truncated; use '--show-trace' to show the full, detailed trace)

       error: The option `clan.core.vars.generators.chris-mail.migrateFact' does not exist. Definition values:
       - In `/nix/store/pwzv0gvph47cya8jdjhp3vnh0dsxq2mh-source/modules/mailserver.nix': "chris-mail"

       Did you mean `clan.core.vars.generators.chris-mail.files', `clan.core.vars.generators.chris-mail.finalScript' or `clan.core.vars.generators.chris-mail.name'?